You obviously dont understand the process of film making!
You CANNOT end a 12 hour trilogy, something which spanned 3 years by having the main characters coming home to even more heartache!
Weve HAD the war, weve HAD the death and despair, a Movie like this needs a happy ending!
How would I as a movie goer have felt if when Frodo returned to the shire it had been destroyed!
The very thing he'd been fighting to protect! It would have been an utterly depressing end and made the entire journey feel pointless!
I'd respectfully suggest you sit down and watch the films again, because in essence that's exactly what happens for Frodo. I know what you are trying to say, and I agree. But that's what makes the films so excellent, so near to perfect as is humanly possible. Acurrately respresenting what happens in the books at the end would have been a huge mistake. You cannot bring the events to a massive crescendo and conclusion only to then embark on a new and ultimately worthless adventure when the 4 hobbits return home and find the Shire destroyed. It just about works in the books as a way to demonstrate how the hobbits have changed aftet their adventures and as a metaphor for the evils of industrialisation. In the films it would have failed. But what the end of the films do show is that through saving Middle Earth Frodo has changed so much that The Shire no longer exists for him, in that The Shire is a metaphor for innocence and youth and Frodo has grown up. Frodo knowingly sacrificed himself in body and mind to destroy the ring and in so doing sacrificed a part of himself. When you watch the films back you can see that process happening and see Frodo is aware of that from quite early on.
Anyway, enough of my ramblings. As a fan of the LotR books and all things Tolkien and a fan of films I can safely say that the films were a worthy respresentation of the books in film form and were among the greatest films ever made. The Hobbit will be every bit as good but very different in fell and look and I for one cannot wait.